Water tank cleaning is an essential practice for the prevention of Legionella. Water testing and chlorination should be carried out regularly as a part of your good water hygiene program. Our engineers have a wealth of experience and knowledge, using a number of different water tank and mains chlorination methods, including gravity feed and direct injection.

The Water Tank Cleaning and Chlorination Process

The standard method for water tank cleaning, is to empty the tank using a submersible pump and hose. The tank is then cleaned using an industrial wet vacuum, followed by a full clean using cloths and a disinfecting solution. The water tank is then refilled and dosed with sodium hypochlorite, to a chlorine level of 50ppm. This solution is then run through each system by opening the relevant taps and valves. The water tank and system chlorination is complete after leaving the solution in the system for one hour. A water system sample is taken to check there is no dramatic drop in chlorine levels, if so the process is repeated. The water tank is then drained and filled with fresh water, this water is then used to flush through the system and remove the chlorine.


Water Mains Chlorination

For closed systems such as water mains, the chlorination of water mains is carried out using a mobile tank and dosing pump. The tank is dosed with a 50ppm sodium hypochlorite solution and connected to the newly installed or existing water main. The chlorine solution is then injected into the water main, ensuring the furthest outlet and any other drawing points are opened in sequence. The discharge from each draw-off point is tested until a minimum 50ppm solution is achieved. The system is then left for one hour, and a number of draw off points are tested. If satisfactory, the mobile tank and dosing pump is removed, and the system can be flushed with mains water until all traces of chlorine are removed.

Water system and water tank cleaning can be carried out with other chemicals, such as chlorine dioxide, which is more effective against Legionella and bio-films. Water chlorination chemicals can also be neutralised, saving large amounts of water and in turn cost. To discuss any requirement you may have for water tank cleaning or mains chlorination, please call our offices on 0345 505 2540.


Why Chlorinate Your Water Main or Supply?

We provide all methods of water chlorination including direct injection and gravity feed to ensure your premises has an excellent level of water hygiene.

We carry out water tank cleaning and chlorination services on a wide range of buildings nationwide. Some of the sectors we serve include:

  • Hospitals & Healthcare
  • Schools & Universities
  • Factories and Process Facilities
  • Farms
  • Commercial Properties

Our Water Main Chlorination Process In Practice

On a recent job carried out at Lower Culham Farm. Our engineers carried out the water tank cleaning and system chlorination on two cottages and a bore hole which supplied them. The bore hole had been contaminated with a high level of e-coli. A full clean of the bore hole was undertaken and a chlorination of the pump sets, pipework and water systems was carried out. As a result we were awarded the contract for all Lower Culham Farm’s water hygiene services.


Water Tank Cleaning & Chlorination Types

  • BS6700
  • L8
  • Hot and Cold Water Systems
  • Mains Systems
  • Booster Tank Systems
  • Both Existing Systems and New Installations